Recently, an imprint technique is coming into practical use as a technique for manufacturing a semiconductor device. In the imprint technique, a resin supplied (coated) onto a substrate is cured in a state in which a mold (original) on which a micropattern has been formed and the resin are brought into contact with each other.
A photo-curing method is known as one of resin curing methods in the imprint technique. In the photo-curing method, a resin pattern is formed on the substrate by performing ultraviolet-light irradiation in a state in which a transparent mold is in contact with an ultraviolet-curing resin to cure and expose the resin to light, and then separating (releasing) the mold.
It is known that if a bubble remains between a mold and a resin on the surface of a substrate with which the resin has been coated when imprinting the mold onto the substrate, a pattern to be formed is distorted. As a measure for this, Japanese Patent Laid-Open No. 2007-509769 discloses a technique of supplying a gas such as helium or carbon dioxide having high diffusibility or high solubility to the resin such that the bubble is less likely to remain between the mold and the substrate, and substituting the gas for air in a gap between the substrate and the mold. Moreover, Japanese Patent Laid-Open No. 2007-509769 discloses a technique of generating a negative pressure in the space between a mold and a substrate and removing a gas serving as the generation source of a bubble. Furthermore, Japanese Patent Laid-Open No. 2009-532245 discloses a technique of sealing the periphery of a mold by providing a gas supply port (air bearing) and a gas recovery port provided on the upper surface of a stage to increase a gas concentration in a gap between a substrate and the mold easily.
However, when imprinting the peripheral portion of a substrate, in particular, the step between the substrate and a portion outside the substrate causes a volume difference in the space between the substrate and a mold, resulting in making difference in a necessary gas amount even within the same shot. Therefore, unevenness occurs in a gas concentration even if a plurality of gas supply units supply the gas equally. This may make it impossible to suppress a transfer failure caused by a bubble. The time for imprint increases and productivity decreases, however, if waiting until the gas concentration becomes uniform.